Add days to date in pandas

Question

I have a data frame that contains 2 columns, one is Date and other is float number. I would like to add those 2 to get the following:

   Index           Date           Days           NewDate
     0           20-04-2016        5           25-04-2016
     1           16-03-2015       3.7          20-03-2015

As you can see if there is decimal it is converted as int as 3.1--> 4 (days). I have some weird questions so I appreciate any help. Thank you !

Solution 1

First, ensure that the Date column is a datetime object:

df['Date'] = pd.to_datetime(df['Date'])

Then, we can convert the Days column to int by ceiling it and the converting it to a pandas Timedelta:

temp = df['Days'].apply(np.ceil).apply(lambda x: pd.Timedelta(x, unit='D'))

Datetime objects and timedeltas can be added:

df['NewDate'] = df['Date'] + temp

Solution 2

You can convert the Days column to timedelta and add it to Date column:

import pandas as pd

df['NewDate'] = pd.to_datetime(df.Date) + pd.to_timedelta(pd.np.ceil(df.Days), unit="D")
df

Comments

[3kstc]

How would one create NewDate by adding Days to today's date? ie df['NewDate'] = ??date_of_today?? + pd.to_timedelta(pd.np.ceil(df.Days), unit="D")

[3kstc]

How would one add on Days to todays date and create a NewDate?

[languitar]

Please open a new question. This is not directly related to the original question.

[3kstc]

I posted a new question

[Rahul Kumar Singh]

cannot add DatetimeIndex and DatetimeIndex

[el Josso]

Best one, for now on, use directly numpy and not from pandas pd.np.ceil(df.Days) --> np.ceil(df.Days)